The IC tag is considered to be a product positioned at the entrance to the ubiquitous age. Name tags, Suica cards, Fe RAM cards, and the like have been developed for RF-ID (microminiaturized radio frequency identification). Many people expect that the IC tag market must grow greatly. However, the IC tag market has not yet grown more than expected. This is because there are social problems that should be overcome, such as price, security, and confidentiality.
It is also expected that the RF-ID technology is applied to the identification of written property, such as paper money and securities. Since the problem of counterfeit bills becomes significant, an IC tag may be embedded in paper money to solve such a problem. However, IC tags are expensive and large. It is therefore difficult to embed an IC tag.
The price of IC tags can be reduced by miniaturizing IC tag chips. The miniaturization of IC tag chips results in an increased number of tag chips produced from a single wafer. So far a 0.4 mm square IC tag chip has been developed. This IC tag chip can store 128-bit memory data that can be read by microwaves of 2.45 GHz (see, for example, Non-patent Document 1).
A paper sheet data management system is disclosed for tracking the source of a counterfeit bill or persons who use the counterfeit bill (for example, Patent Document 1). The system reads and stores specific data recorded for each paper money, and tracks the source data of the counterfeit bill and manages the data. In this paper sheet data management system, when a paper money in which specific data has been recorded is returned from a reader after the reader reads and stores the specific data, the recorded specific data is transferred to the place where the paper money is transferred.    Patent Document 1: Japanese Unexamined Patent Application Publication No. 11-328493    Non-patent Document 1: Mitsuo USAMI “An ultrasmall RFID chip: μ-chip”, OYO BUTSURI, Vol. 73, No. 9, 2004, pp. 1179-1183
In the data management system disclosed in Patent Document 1, when a paper money is returned from the reader, the specific data is transferred with the paper money. It cannot be found that a counterfeit bill has been used, until the data is transferred to the place where the paper money is returned. Thus, the specific data of the paper money cannot be grasped or managed in real time immediately after the specific data has been read. It is difficult for the manager to grasp the use of a counterfeit bill immediately.